Engine lubricating system



May 17, 1960 Filed Oct. 1, 1954 E. B. ETCHELLS ETAL ENGINE LUBRICATINGSYSTEM 5 Sheets-Sheet 1 INVENTORS a fizraw wwawek ATTORNEY y 17, 1950 vE. B. ETCHELLS ET AL 2,936,857

ENGINE LUBRICATING SYSTEM I Filed Oct. 1, 1954 5 Sheets-Sheet 2 av errZ5411 ATTORNEY May 17, 1960 E. B. ETCHELLS ETAL 2,936,357

ENGINE LUBRICATING SYSTEM Filed Oct. 1. 1954 5 Sheets-Sheet 3 INVENTORSATTORNEY E. B. ETCHELLS ETAL 2,936,857

ENGINE LUBRICATING SYSTEM 5 Sheets-Sheet 4 May 17, 1960 Filed Oct. 1.1954 M a new V 1 m wmmmlh H a zmfiwnmm 2 m3 m 1 3 May 17, 1960 E. B.ETCHELLS ET AL 2,936,357

ENGINE LUBRICATING SYSTEM Filed Oct. 1, 1954 5 Sheets-Sheet 5 INVENTORSATTORNEY United States A Patent- 2,936,857 7 ENGINE LUBRICATING SYSTEMEugene B. Etchells, Birmingham, Adelbert E. Kolhe, De-

troit, and Harry F. Barr, Franklin, Mich., assignors to General MotorsCorporation, Detroit, Mich., a corporation of Delaware a ApplicationOctober 1, 1954, Serial No. 459,668

1 Claim. (Cl. 184- 6) This invention relates to lubricating systems forinternal combustion engines and has particular relation to lubricatingsystems for V type internal combustion engines for automotive and otheruses.

It is proposed to improve the lubricating system and simplify theconstruction and service of an internal cornbustion engine by changingthe construction of the-oil pump so that the structure may be moreeasily con structed, assembled and serviced; by changingthe lubricationof the main bearings for the crankshaft of the engine so that anincreased load may be carried by the bearings without increasing thesize of the bearings; by changing the lubrication of the connecting rodbearings so that the bearings may be properly lubricated at lowerpressures; by limiting the quantity of the oil supplied to the engagingsurfaces of the cylinders and pistons; by supplying oil at reducedand-equal pressures from a main supply gallery employed in lubricatingthe crankshaft and camshaft bearings to distribution galleries employedin lubricating the valve actuating mechanisms for the different banks ofcylinders of an engine; by employing oil previously used in lubricatingthe lower endof the distributor shaft for lubricating the gears employedin.

driving the shaft, by simplifying the lubrication of the timing gearmechanism and by improving the lubrication and the control of thelubrication for the valves, the valve springs, the rocker arms and thepush rods constituting the valve actuating mechanisms for each bank ofcylinders of the engine.

In the drawing:

Figure 1 is a longitudinal sectional view of an engine.

having a lubricating system embodying the features of the invention.

Figure 2 is a cross-sectional view of the enginedisclosed by Figure 1.

Figure 3 is anenlarged fragmentary view of thefront of the engine withparts broken away and shown in crosssection to better illustrate themeans by which oil is supplied to the engine and by which the timinggear mechanism of the engineis lubricated.

Figure 4 is a fragmentary cross-sectional view taken. through the rearcrankshaft and camshaft bearing. of the.

substantially in the plane of lines 6-6 on Figure 4 and illustrating thestructure involved in lubricating the lower end of the distributor shaftand the driving mechanism for the distributor shaft.

2,936,857 Patented May 17, 1960 Figure 7 is a fragmentary longitudinalsectional view through the rear end of the engine further illustratingthe structure shown by Figure 4.

Figure 8 is an enlarged view of a part of the valve actuating mechanismfor one of the cylinders of the engine and illustrating particularly theengaging ends of the push rods and rocker armse'mployed in the valveactuating mechanism of the engine.

Figure 9 is a diagrammatical illustration of a crankshaft andillustrating at a), (b), (c) and (d) the lubrication of the main andconnecting rod bearings at different positions during each revolution ofthe; crankshaft.

The engine 10 embodying the invention comprises an engine block 11 inwhich rows or banks 12 and 13 of obliquely disposed cylinders 14 areformed. The rows of cylinders 14 are adapted to be closed by heads 16which may be removably secured'to the cylinder banks 12 and 13 by bolts17. The manifold structure 18 is secured to the adjacent sidesof theheads 16 and to the ends of the block 11 by bolts '19.

The cylinders 14 are adapted to receive reciprocating tern for theengine is adapted to be stored in the sump 26. The lubricating oil maybe supplied to the engine through a filler tube 27 whichmay be securedin an opening in the manifold 18 in position to communicate with acavity 28 formed-in the block 11 and having an opening 29 through thefront wall of the block and leading to the timing gear compartment 30which is enclosed within a cover 31 secured by any suitable means to thefront wall of the block 11. The lower extremity of the compartment 30communicates with the crankcase 20 of the engine through an opening 32formed between the front main bearing of the engine and the oil pan 24.It will be apparent that oil poured into the filler tube 27 will flow bygravity to the oil sump 26 through the cavity 28-, the opening 29, thecompartment 30, the opening 32 and the front and downwardly sloping endof the oil pan 24. A horizontally disposed baffle 33 is welded orotherwise secured to the oil pan 24 by side flanges 34. The bafile 33tends to close the front end of the sump- 26 thereby largely preventingsurg ing of the oil in the sump 26 throughout the oil pan 24 undercertain conditions of operation of the engine.

An oil pump 36 for circulating oil in the lubricating.

be secured to' or removed from the engine by operation In order that thepump of a single bolt indicated at 39. 36 may be installed and removedby operation of the bolt 39 it is proposed to form the casing 38 toprovide an enlarged boss 41 adjacent the outlet passage 42 leading fromthe pump and through the central part of which it is proposed to providean elongated opening for receiving the bolt '39. The bolt 39 is adaptedto project through the open in the boss 41 and into a threaded openingformed centrally within an enlarged projection 43 extending downwardlyfrom bearing cap 44 for the rear main bearing 46 of the engine. Thebearing cap 44 is removably secured to the upper part of the rear mainbearing 46 by bolts 47. It is proposed to construct the bolt 39 so thatit will be large enough to withstand all of the stresses involved insupporting the oil pump' 36 on the bearing cap 44. However, in order toeliminate any possibility that the pump 36 may tend to rotate. on thebolt 39 it is proposed to provide a small dowel pin 48 which may belocated in aligned openings in the boss- 41 and the projection 43 atoneside of and parallel to the openings for the bolt 39. It will beapparent that even a small pin made to closely fit the opening. in whichit is tightly but removably secured, will be sufficient to preventrotation of the pump 36 upon the hearing cap 44. The opening in the,projection 4.3 for the pin 48 may be made to fit the pin somewhat moretightly than the opening in the boss 41. This will cause the pin toremain in the projection 43 when the bolt 39 is removed and the pump isremoved from the bearing cap 44. It will be apparent that the laborinvolved in removing and installing the oil pump 36 by manipulating thebolt 39 will be much less than has been required heretofore with two ormore bolts. It will also be apparent that the labor and materialsinvolved in providing one larger bolt in place of a plurality of smallerbolts Will not be proportionally greater.

The crankshaft 49 for the engine is supported in the block 11 by rearmain bearing 46 and by a plurality of spaced and forwardly disposed mainbearings 51. Each of the main bearings 46 and 51 may be provided withbushings 52 which may be constructed in upper halves and lower halveswith the upper halves being removably secured in the upper half of eachmain bearing and the lower halves being removably secured in the bearingcap for each bearing. The forwardly disposed bearings 51 may bepositioned between adjacent crankarms 53 of the crank shaft 49 and mayhave removable bearing caps 54 secured thereto by bolts 56. The bearings51 may be made shorter than therear main bearing 46 to decrease thelength of the engine.

In order to lubricate the bearings for the crankshaft 49 it is proposedto provide a peripheral groove 57 midway betweenthe axially disposedends of the upper half of each of the bushings 52. Oil under pressurefrom the pump 36 may be supplied to the middle of each of the grooves 57for the bearings 51 by oil passages 58 which are formed in the front endwall 59 and in the transversely disposed intermediate walls 61 of theblock 1 1. The oil supplied to the grooves 57 is supplied to the uniformclearances between the journals and the bearings which extend from themiddle toward the opposite ends of the bearings and the journals,thereby uniformly metering the oil toward the axially disposed ends ofthe bearing. The passages 58 are supplied with oil by a supply galery 62formed in a column 63 and extending throughout the length of the blocklll, between the cylinder banks 12 and 13 and between the crankcase 29and the camshaft gallery 64 of the engine 10. The rear end of the maingallery 62 is supplied with oil by passages 67 and 68 which are formedin the rear wall 69 of the block 11. The lower end of the passage 68communicates with a passage 71 formed in the bearing cap 44 andcommunieating with outlet passage 42 from the pump 36 through a cavity72 formed between the plane engaging surfaces of the projection 43formed on the bearing cap 44 and the boss 41 formed on the pump casing38. Oil for supplying the groove 57 in the bushing 52 for the rear mainbearing 46 is supplied by a passage 73 communieating with the supplypassage 68. It will be apparent that if the oil grooves 57 extend onlythroughout the circumferential length of the upper halves of thebushings 52 and terminate at the adjacent ends of the lower halves ofthe bushings 52, the lower halvw will provide larger bearing surfacesfor supporting the journals of the crankshaft 49 than the upper halvesof the bushings 52. However, it will be further apparent from examiningthe en.- gine in the position illustrated by Figure 2 that the greatestload applied to the journals of the crankshaft 49- is applied when thepistons 21 are at or near the outer or upper dead center positions ofthe pistons in the cylinders 14 and that the smallest load is appliedwhen the pistons. 21 are at or near the inner or lower dead centerpositions of the pistons in the cylinders 14; This maximum load will beapplied only to the lower halves of the bushings 52 so that removing thelubrication grooves from the lower halves of the bushings 52 actuallydecreases the unit load on the lower halves of the bushings 52 when themaximum load is applied thereto by the journals of the crankshaft 49. Byleaving out the oil grooves in the lower halves of the bushings 52 ithas been found possible to greatlyincrease the, horsepower of the enginewithout increasing the length of the engine and without increasing themaximum unit load upon the bearings of the engine. It has been foundthat the bearings are lubricated just as well'with an oil groove"supplied with oil under pressure only in the upper half of each of thebearing sleeves. The journals of the crankshaft 49 each rotatethroughout the length of the grooves 57 and consequently pick up oilfrom the grooves on all parts of the exterior surfaces thereof. Alsosince the maximum unit bearing pressure may decrease on the lower halvesof the bearings, the thickness of the oil film on the lower halvesactually may be greater than it would be with oil grooves in the lowerhalves of the bearings. V

112 has also been discovered that the connecting rod bearings and thecylinders may be properly lubricated by oil supplied from the grooves57in the upper halves of the bushings 52. To do this it has been founddesirable to change the angular positions of the passages in thecrankshaft and by which oil has been supplied to the connecting rodbearings from the main bearings of the crankshaft. It is novv proposedto position these passages obliquely with respect to the radial planethrough the axis of the crankshaft and the axis of the crankpin of eachcrankarm 53 of the crankshaft 4-9 as is indicated at 74. The passages 74also extend from midway between the ends of the crankshaft bearings tomidway between the ends of the connecting rod bearings. Instead of beingpositioned in the radial plane of each of the crankarms the passages 74are positioned to intersect the radial plane of each crankarmsubstantially midway between the ends of each passage 74. As isillustrated by Figure 9 it is proposed to have the ports at the oppositeends of the passages 74 lead the radial plane of each crankarm in thedirection of rotation of the crankshaft by a considerable number ofdegrees so that when any piston is in outer dead center position'withrespect to the crankshaft the outlet end of each passage 74 will besubstantially beyond the middle ofthe connecting rod bearing and theinlet end thereof will be near the leading end of one of the oil grooves57. Position (a) in Figure 9 illustrates a crankarm 53 at the outer deadcenter position of the piston with the outlet end of port 74 beyond theradial plane of the crankarm, the radial plane extending through theaxis of the shaft and the crankpin of the crankarm and beyond theleading end of the groove 57. It will be noted that the outlet end ofthe passage 74 is considerably beyond the middle of the connecting rodbearing and that the inlet end of the passage 74 is in communicationwith the leading end of the groove 57.

extent of the bushing 52 and since the outlet end of passage 74 isalways beyond the position where there, is a minimum clearance betweenthe crankpin and the connecting rod bearing, it will be apparent thatthe passage 74 will supply oil to the clearance space between thecrankpin and the connecting rod bearing throughout at least of rotationof the crankshaft 49. This 180 5. of rotation of the erankshaftwillloccur when the clearance between the crankpin and the connectingrod bearing increases from minimum to maximum clearances. It will beapparent that the oil in the bearing will tend to flow outwardly towardthe axially disposed ends of the bearing substantially throughout theentire clearance in the bearing. Since the crankpin rotates throughout360 within the connecting rod hearing it will be apparent that theentire peripheral surface of the crankpin will be supplied with oil fromthe clearance space between the crankpin and the connecting rod bearing.Notwithstanding that the passage 74 is not in communication with thegroove 57 in positions (c) and (d) it will be apparent that the passage74 is filled with oil and that centrifugal force resulting from rotationof the crankshaft may cause the oil to tend to flow from the outlet endof the passage 74. This also will tend to lubricate the connecting rodbearing because this will reduce the oil pressure in the main bearing atthe inlet end of the passage 74 and will tend to cause oil that has beensqueezed from the'main hearing to flow inwardly of the main bearing andinto the inlet end of the passage 74.

As will be apparent from Figure 2, a slot 76 is formed in one side ofeach of the connecting rod bearings between the surfaces where thebearingrcaps 75 are bolted at 77 to the rod end part of each connectingrod 22. The

92 that intermittently communicates with an axially ex tending slot 93that is formed in thejournal of the cam shaft and which terminates inspacedrelation to the ends of the bushing 91. The rotation of the slot93 with the shaft 81 will apply the'oil supplied by the opening 92 andthe passage 89 to the interior surface of the bushing 91.. The bushing91 also is provided with openings 94' which are located in axialalignment with the opening 92 and at the opposite end of the groove 93.An annular groove 96 formed in the bearing 82 around the bushing 91 andin a position to communicate with the openings 94 is connected by theslot 93 to the passage 89 once during each revolution of the camshaft81. Since the oil is supplied to the groove 96 only once during eachrevolution of the camshaft 81 it will be apparent that the pressure inthe groove 96 will not be as great as outlet ends of the passages 74'approach the slots 76 as the I slots 76 are directed toward thecylinders 14in the bankof cylinders opposite that to which theconnecting rod 22 operates one of the pistons 21. When the passage 74 soregisters with one of the slots 76 the oil in the passage 74 is forcedoutwardly by centrifugal force and thereby discharges a spray of oil onthe opposing cylinder 14 and substantially entirely across the opposingcylinder 14. Figure 2 illustrates one of the slots 76 in position tospray oil from the passage 74 on one of the cylinders in the bank ofcylinders 13. However, the slot 76 shown by Figure 2 is in a connectingrod 22 for one of the cylinders in the cylinder bank 12. The connectingrods 22 for the cylinders in the bank of cylinders 13 also are providedwith slots 76 which register with the passages 74 to spray oil on thecylinders in the cylinder bank 12 when the crankshaft is in the properposition. Position (c) in Figure 9 represents one of the passages 74approaching the slot 76 as shown by Figure 2. Position (d) in Figure 9illustrates the position of one of the passages 74 as it approaches aslot 76 in one of the connecting rods for the bank of cylinders 13 whenthe slot is in a position to lubricate one of the cylinders in the bankof cylinders 13.

It will be apparent from the foregoing that the invention provides asimple, inexpensive and effective means for lubricating the mainbearings, the connecting rod bearings and the pistons and cylinderswhile decreasing the maximum unit pressure affecting the main bearings.This is done without increasing the length of the engine or the expenseinvolved in manufacturing the engine.

The camshaft 81 of the engine also is supported in a bearing 82 formedin the rear wall 69. In front of the bearing 82 are intermediatebearings83 formed in the transverse walls 61 and front bearing 84 formedin the front wall 59, the latter bearings also supporting the camshaft81. The bearings 83 and 84 of the camshaft the pressure in the mainsupply passage 62. The oil at reduced pressure in the groove 96 issupplied to tappet or valve actuating mechanism galleries 97 and 98 byconnecting passages 99. The galleries or passages 97 and 98 are disposedin columns 101 which extend substantially throughout the length of theblock 11 and are positioned on opposite sides of the column 63 in whichthe main supply passage 62 is formed. The columns 101 and 63 merge withone another to form a web 102 that extends across the block 11 betweenthe lower parts of the cylinder banks 12 and 13 and above the camshaft81.

Immediately in front of the bearing 82 the passage 97 is intersected bya cavity 103 which is formed in the block .11 for receiving an elongateddistributor shaft casing 104. The casing 104 forms a lower part of thecasing of the ignition distributor 106 which is mounted at the are alllubricated by oil supplied by the passages 58 from a the main supplypassage 62. To accomplish this the bearings 83 and 84 each may beprovided with bushings 86 around which annular grooves 87 which formparts of the passages 58 are formed in the bearings 83 and 84. From thegrooves 87 the journals of the camshaft are lubricated by openings 88formed in the bushings 86 in diametrically opposed relation to oneanother and in alignment with the passages 58. The rear bearing 82 ofthe camshaft is supplied with oil by a passage 89 which is formed on therear wall 69 and which communicates with the main supply passage 62. Thebearing 82 has .a bearing sleeve 91 which rear of the engine and whichcontrols the ignition of the charges in the cylinders of the engine. Thetubular casing 104 has enlarged cylindrical bosses 107 and 108 formedtherein which are adapted to form a relatively tight but removable fitwithin'i'nwardly disposedflanges 109 formed on the block 11 at theopposite ends of the cavity 103. The bosses 107 and 108 are the guidingmeans by which the distributor shaft casing 104 is mounted within theblock of the engine. It will be noted that the boss 108 is disposed inthe inwardly disposed flange 109 in such a way as to intersect thepassage 97 between the upper and lower extremities of the boss 108.However, in order to provide a continuation of the passage 97 across theboss 108, the boss 108 is formed to provide an arcuate groove 11 1midway between the upper and lower ends of the boss 108." The groove 111is substantially as large in cross-sectional area as the passage 97 soas not to interfere with the flow of oil in the passage 97. However, theparts of the boss 108 above and below the groove 111 tightly fit theflange 109 and therefore prevent leakage of oil from the groove 111 andthe passage 97 upwardly and downwardly within the cavity 103. Thedistributor shaft 112 extends downwardly within the casing 104 and atthe lower end thereof is rotatably mounted in a bushing 1 13. Thebushing 113 and the shaft 112 therein are lubricated by a passage 114that extends across the boss 108 and the bushing 1113 between thearcuate groove 111 and the shaft 112. The passage 114 is located betweenthe upper and lower ends of the bushing 113 but somewhat nearer theupper than the lower end of the bushing 113. Within the bushing 113 theoil supplied by the passage 114 will flow upwardly and downwardlytherefrom by surface tension and capillary attraction. The oil whichflows upwardly within thebushing 113 will collect around the shaft 112at the upper end of the bushing 113 where it will drain outwardly of thecasing 104 through a passage 116. The outer end of the passage 116communicates with the upper end of passage 117 which is formed withinthe flange 109 and axially of the shaft 112 by forming a plane surface118 on one side of and throughout the lengthof the boss 108. The oilfrom the passage 116 will flow downwardly by gravity in the passage 117for.

the purpose of lubricating thrust bearing 1'19 and gear 121' located atthe lower end of the shaft 112. The gear 121 is formed on the upper endof a sleeve 122 which is Secured in any suitable manner to the lower endof the shaft 112 beyond the casing 1114. A thrust washer disposedbetween the upper end of the sleeve 122 and the lower end of the casing1114 forms the thrust bearing 1'19. The gear 121 is adapted to mesh withgear 123 located on the camshaft '81 in front of the bearing 82 fordriving the distributor shaft 112 through the gear 121. It will beapparent that the oil supplied by the opening 116 will not onlylubricate the thrust bearing 119 and the gear 121 but will alsolubricate the teeth of the gear 123 on the camshaft 81. The oil thatflows downwardly within the bushing 113 from the opening 114 will followthe shaft 112 and will lubricate the coupling 124 between the lower endof the shaft 112 and the'shaft 126 which drives the oil pump 36. Thecoupling 124 is of a conventional tongue and slot construction and isformed within the lower extremity of the sleeve 122.

The timing sprocket or gear 127 which drives the cam shaft 81 is securedon the front end of the camshaft by a pin 128' and a plurality of bolts129. The hub 131 of the gear 127 rotates against the front end of thecamshaft bearing 84. To lubricate the relatively rotating surfaces ofthe hub 131 and the end of the bearing 84 the hub 131 is provided with aplurality of radially disposed slots indicated at 132. The innerextremities of the slots 132 terminate at the end of the bushing 86 forthe camshaft bearing 84. Oil that is supplied to the bearing 84 by thepassage 58 and the annular groove 87 will flow in opposite directionsfrom the openings 33 and some of the oil will collect at the front endof the bushing 86. The oil so collected will lubricate the engagingthrust surfaces of the hub 131 and the bearing 84 and the oil whichcollects in the slots 132 will be thrown outwardly' by centrifugal forceand against the rim of the gear 127 and the timing chain 133. Timingchain 133 drives the gear 127 through gear 134 which is mounted on thefront end of the crankshaft 49.

The distribution passages for galleries 97 and 98 extend through theblock 11 in such a way as to intersect the. openings in the bosses 136in which the valve lifters 137 for the engine are mounted. However, thelifters are provided with annular grooves 133 which provide for thecontinuous flow of oil in the passages 97 and 98'. The oil is suppliedto the interior of the lifters 137 by passages 139 which communicatewith the grooves 138. The lifters 137 may be of any desired form but inthe present instance may be hydraulic lifters as disclosed by Papenguthapplication Serial No. 433,990 filed in the United States Patent Officeon .lune "2, 1954, and issued as Patent 2,818,056. It is consideredpreferable to employ valve lifters through which oil may be supplied topassages 141 formed throughout the length of push rods 142 which areadapted to operate between the valve lifters 137 and rocker arms 143 foroperating the valves of the engine. in the present instance one rockerarm. 143 is provided for the inlet valve 144 and one for the exhaustvalve 146 for each cylinder of the engine 10. The rocker arms 143 aresupported on the heads 16 of the. engine by pins 147, the upper ends ofwhich carry hemispherical bearings 148 that engage sockets 149 extendinginwardly between the opposite ends of the rocker arms 143. As is bestshown by Figure 8 the rocker arms 143 are provided with sockets 151 atthe push rod engagingends thereof and in which the upper ends of thepush rods 142 are seated. In order to supply oil to the interior of thesockets 151 the upper ends of the push rods 142 are. provided withaxially disposed openings 152 through which the oil from the push rodsis supplied to the. clearance space between the ends of the push rodsand the sockets 151. In order to provide bearing en'- gagement betweenthe push rods and the sockets and to l V s u. v provide means forlubricating the sockets 109' and the valve springs 153 with which thevalves14'4 and 106 are provide'cLit is proposed to form the socketengaging ends or" the, push rods 142 and the push rod engaging surfacesof the sockets 151 in such manner as to provide cavities "154 within thebearing. surfaces between the,

of rotation ofgreater radii of curvature than the radii;

This may be done by making the center of the radii of curvature ofcurvature of the ends of the push rods.

of the end of the rod 142 at 156 whereas the centers of curvature of thetwo arcuate surfaces forming the socket 151 are at 157. The lines 158represent theopposite extremes of movement of the circular linesofcontact between the sockets 151 and the end of the push rods 142. It isproposed to provide passages 159 through the sockets 151 in such aposition that the circular lines of contact between the push rods andthe sockets will always be adjacent the outer edge of the passage 159.The opposite edges of the passages 159 will extend beyond the circularlines of contact and will overlap the cavities 154 between the ends ofthe:

push rods and the sockets; The passage 159 therefore will be in aposition to supply oil to the opposite surface of the rocker arms 143within the limit of the capacity of the small clearance at the outerperipheral edges of the cavities 154. However, the passages 159 arepositioned far enough away from the passages 152 to avoid overlapping.The oil supplied by the passages- 152 therefore will be at all timesmetered to the pas-' sages 159 through the small clearance spaces at theedges of the cavities154 and adjacent the circular lines of contactbetween the ends of the push rods and the sockets.

The oil which is supplied to the outer surface of the rocker arms 143 bythe passages 159 will move by surface tension downwardly into thesockets 149 to lubricate the surfaces between the sockets and thebearings 148. The excess oil will be discharged from the sockets 149through the clearance openings 161. However, some of the oil will moveby surface tension toward the opposite ends of the push rods 143 andwill lubricate the valve springs 153 and the outer ends of the valvestems for the valves 144' and 146 by moving over the flanged edges ofthe rocker arms 143 at the valve engaging ends thereof. This will be anextremely limited and metered quantity of oil but it will be suflicientto lubricate the valve stems and the valve springs and it will notsupply excess oil to such an extent as to interfere with the operationof the engine. Some of the oil supplied to the ends of the valve stemswill move by surface tension through the valve spring washers 162 and bymoving down the stems of the valves 144 and 146 will lubricate theguides 163 in which the valve stems are mounted in the heads 16. Thevalve springs '15?) may be provided with internally disposed sleeves 164to insure that an excess amount of oil is not supplied to the valveguides 163.

The claim:

An internal combustion engine comprising an engine frame having acylinder and a bearing formed therein and having a reciprocably mountedpiston in said cylinder, 2. crankshaft :having a journal rotatablymounted in said bearing and having a crankarm formed to provide acrankpin, a connecting rod connecting said crankpin and said piston,said bearing on one side thereof and adjacent said cylinder being formedto provide an arcuate groove extending inwardly from the bearing surfacethereof and circumferentially around said one side of said bearing,said. groove being located midway between the axially disposed ends ofsaid bearing and having, end extremitiesterminating in circumferentiallyspaced relation, said heating between saidaxially disposed'ends and onthe opposite sides of said groove and on the-,side of said bearingopposite said groove being formed to provide a smooth and continuousbearing surface, said bearing surface and the surface of saidjournalproviding uniform clearance means between the two throughout the lengthof said bearing, means supplying lubricating oil to said groove andmaintaining an oil film within said clearance and throughout the extentof said bearing and journal surfaces, said uniform clearancesubstantially uniformly metering said oil in .said film from said groovetoward each of the bearing ends, a passage formed in said crankshaft andextending obliquely across said crankshaft from an inlet port in saidjournal to an outlet port in said crankpin midway between the ends ofsaid crankpin, said inlet port and said outlet port being disposed onopposite sides of a radial plane through the axes of said'crankpin andsaid journal with said outlet port leading said radial plane and saidinlet port leading said radial plane in the direction of rotation ofsaid crankshaft, said passage rotating with said crankshaft andconnecting the clearance space between said crankpin and said connectingrod bearing to said groove after said piston reaches outer dead centerposition in said cylinder and during the movement of said inlet portthroughout the circumferential extent ofsaid groove.

UNITED STATES PATENTS Eames Jan. 10, 1911 Mead Sept. 5, 1922 KrenzkeJune 7, 1927 Bower May 19, 1931 Vincent Sept. 15,1931 Loeflier Dec. 1,1931 Fahrney Mar. 7, 1933 Iacoby May 23, 1933 LOrange, Aug. 6, 1935Frelin May 7, 1940 Frank Nov. 29, 1949 Good Sept. 25, 1951 Davis Oct.23, 1951 Antonsen Nov. 8, 1955 FOREIGN PATENTS Germany Feb. 28, 1927Germany Sept. 6, 1938 Great Britain Ian. 10, 1946 Switzerland Mar. 17,1952

